The present invention relates generally to systems for monitoring thermal cooling in electronic devices and, more particularly, to a heat protection apparatus for protecting computer chips which monitors large increases in electronic resistance in the proximity of a computer chip.
A heat sink and fan are standard components within a computer system housing. The heat sink has multiple surfaces for dissipating heat generated by the computer chip and the fan disperses that dissipated heat. However, fan failure is a typical culprit for an increase in the temperature of a computer chip which ultimately leads to its premature demise. Various thermal monitoring devices have been proposed in the art which monitor a cooling fan, such as by monitoring fan wheel or air flow velocity. However, there are causes of a heat increase other than total fan failure, such as an increase in fan motor heat prior to failure, electrical surge, or an overall increase in ambient air temperature. Existing thermal detection devices for computer components do not adequately detect thermal increases caused by all possible sources.
Therefore, it is desirable to have a heat detection apparatus which provides a fast response to a predetermined temperature occurring along a continuous path in the proximity of a computer chip. Further, it is desirable to have a heat detection apparatus which detects an average temperature rate of rise that is greater than a predetermined rate of rise parameter.
A heat protection apparatus for protecting a computer chip according to the present invention includes a heat sink adapted to be mounted to a computer chip such as a central processor unit or other logic controller chip package. The heat sink includes multiple surfaces configured so as to dissipate heat generated by the computer chip during operation. The apparatus includes a cooling fan mounted to the heat sink for dispersing the dissipated heat into the surrounding ambient air. The heat sink includes a base in close proximity to the computer chip when mounted thereto, the base defining a channel about its lower peripheral edges. The apparatus includes a programmable logic circuit capable of evaluating electrical resistance input data supplied to it and comparing this data to predetermined parameters. The apparatus further includes a solid conductive positive temperature coefficient of resistance (PCTR) polymeric tape having opposed edges in contact with and enveloping respective conductors. The conductors are laterally spaced apart and the polymeric tape spans therebetween. The conductors and polymeric tape, also referred to herein as xe2x80x9cthe sensorxe2x80x9d, are positioned within the channel of the heat sink base and are characterized by changes in electrical resistance corresponding to temperature changes.
The conductors provide electrical resistance input data from the polymeric tape to the logic circuit for evaluation. The polymeric tape is capable of a massive increase in electric resistance at a predetermined temperature experienced therealong. When the resistance input data is evaluated by the logic circuit, an alarm is energized when the evaluated electric resistance is greater than a predetermined programmed critical resistance parameter. The logic circuit further includes a memory for storing resistance input data so that it can calculate and evaluate an average temperature rate of rise relative to the polymeric tape. The alarm is energized if the evaluated temperature rate of rise is greater than a predetermined rate of rise parameter. The alarm may be audible or may be in the form of a visual indicator that may be displayed upon the computer""s display. It should also be appreciated that the computer chip being protected may itself serve as the logic circuit.
Therefore, a general object of this invention is to provide a heat protection apparatus which provides a swift warning when the temperature of a PTCR polymeric sensor positioned in close proximity to a computer chip and heat sink exceeds a predetermined critical temperature.
Another object of this invention is to provide a heat protection apparatus, as aforesaid, which energizes an alarm when an average temperature of a PTCR polymeric sensor positioned in proximity to a respective computer chip and heat sink rises at a rate greater than a predetermined rate of rise parameter.
Still another object of this invention is to provide a heat protection apparatus, as aforesaid, in which a PTCR polymeric sensor extends completely around a heat sink mounted to a computer chip to be protected.
Yet another object of this invention is to provide a heat protection apparatus, as aforesaid, that is easy and economical to manufacture and use.
A further object of this invention is to provide a heat protection apparatus, as aforesaid, which operates whenever a computer system in which the apparatus is installed is energized.
A still further object of this invention is to provide a heat protection apparatus, as aforesaid, having an audible or visual alarm to alert a user when a heat event is detected.
Another object of this invention is to provide a heat protection apparatus, as aforesaid, having a logic circuit that is programmable according to predetermined and user-selectable heat parameters.
Other objects and advantages of this invention will become apparent from the following description taken in connection with the accompanying drawings, wherein is set forth by way of illustration and example, embodiments of this invention.